Dr. Davids on Results of Obinutuzumab With Ibrutinib in CLL

Matthew S. Davids, MD, MMSc, associate director, Dana-Farber Cancer Institute, Center for Chronic Lymphocytic Leukemia (CLL), discusses the initial results of a phase Ib study of ibrutinib (Imbruvica) in combination with obinutuzumab (Gazyva) in patients with relapsed or refractory CLL.

The first 28 patients of this trial were randomized to 3 arms. The results have been interesting in terms of the difference in infusion reactions, explains Davids. In the first arm with single-agent obinutuzumab, there was a 63% rate of infusion reactions. In arm B, there were no infusion reactions, and in arm C there was 1 reaction, which was dramatically less than expected.

Even though the trial is not completely accrued, there is a clear signal to start ibrutinib before or at the same time as obinutuzumab.

In terms of efficacy, the results also seem promising across the different arms. There is a high rate of radiographic complete remission. Davids says that this will be an effective combination and inform the design of future combination studies, and physicians will be able to sequence ibrutinib and obinutuzumab in the optimal way for patient safety and efficacy.